From 516b2e7c2661615ba5d5ad9fb584f068363502d3 Mon Sep 17 00:00:00 2001 From: David Chinner Date: Mon, 18 Jun 2007 16:50:48 +1000 Subject: [PATCH] [XFS] Fix remount,readonly path to flush everything correctly. The remount readonly path can fail to writeback properly because we still have active transactions after calling xfs_quiesce_fs(). Further investigation shows that this path is broken in the same ways that the xfs freeze path was broken so fix it the same way. SGI-PV: 964464 SGI-Modid: xfs-linux-melb:xfs-kern:28869a Signed-off-by: David Chinner Signed-off-by: Christoph Hellwig Signed-off-by: Tim Shimmin --- fs/xfs/linux-2.6/xfs_super.c | 2 +- fs/xfs/linux-2.6/xfs_vfs.h | 14 ++++++++++ fs/xfs/xfs_vfsops.c | 53 +++++++++++++++++++++--------------- 3 files changed, 46 insertions(+), 23 deletions(-) diff --git a/fs/xfs/linux-2.6/xfs_super.c b/fs/xfs/linux-2.6/xfs_super.c index 05f188ed12..06894cf00b 100644 --- a/fs/xfs/linux-2.6/xfs_super.c +++ b/fs/xfs/linux-2.6/xfs_super.c @@ -664,7 +664,7 @@ xfs_fs_sync_super( * occur here so don't bother flushing the buftarg (i.e * SYNC_QUIESCE) because it'll just get dirty again. */ - flags = SYNC_FSDATA | SYNC_DELWRI | SYNC_WAIT | SYNC_IOWAIT; + flags = SYNC_DATA_QUIESCE; } else flags = SYNC_FSDATA | (wait ? SYNC_WAIT : 0); diff --git a/fs/xfs/linux-2.6/xfs_vfs.h b/fs/xfs/linux-2.6/xfs_vfs.h index cb7b0d62fb..dca3481aaa 100644 --- a/fs/xfs/linux-2.6/xfs_vfs.h +++ b/fs/xfs/linux-2.6/xfs_vfs.h @@ -94,6 +94,20 @@ typedef enum { #define SYNC_IOWAIT 0x0100 /* wait for all I/O to complete */ #define SYNC_SUPER 0x0200 /* flush superblock to disk */ +/* + * When remounting a filesystem read-only or freezing the filesystem, + * we have two phases to execute. This first phase is syncing the data + * before we quiesce the fielsystem, and the second is flushing all the + * inodes out after we've waited for all the transactions created by + * the first phase to complete. The second phase uses SYNC_INODE_QUIESCE + * to ensure that the inodes are written to their location on disk + * rather than just existing in transactions in the log. This means + * after a quiesce there is no log replay required to write the inodes + * to disk (this is the main difference between a sync and a quiesce). + */ +#define SYNC_DATA_QUIESCE (SYNC_DELWRI|SYNC_FSDATA|SYNC_WAIT|SYNC_IOWAIT) +#define SYNC_INODE_QUIESCE (SYNC_REMOUNT|SYNC_ATTR|SYNC_WAIT) + #define SHUTDOWN_META_IO_ERROR 0x0001 /* write attempt to metadata failed */ #define SHUTDOWN_LOG_IO_ERROR 0x0002 /* write attempt to the log failed */ #define SHUTDOWN_FORCE_UMOUNT 0x0004 /* shutdown from a forced unmount */ diff --git a/fs/xfs/xfs_vfsops.c b/fs/xfs/xfs_vfsops.c index 3a647339f4..c343fde10e 100644 --- a/fs/xfs/xfs_vfsops.c +++ b/fs/xfs/xfs_vfsops.c @@ -640,7 +640,7 @@ xfs_quiesce_fs( * we can write the unmount record. */ do { - xfs_syncsub(mp, SYNC_REMOUNT|SYNC_ATTR|SYNC_WAIT, NULL); + xfs_syncsub(mp, SYNC_INODE_QUIESCE, NULL); pincount = xfs_flush_buftarg(mp->m_ddev_targp, 1); if (!pincount) { delay(50); @@ -651,6 +651,30 @@ xfs_quiesce_fs( return 0; } +/* + * Second stage of a quiesce. The data is already synced, now we have to take + * care of the metadata. New transactions are already blocked, so we need to + * wait for any remaining transactions to drain out before proceding. + */ +STATIC void +xfs_attr_quiesce( + xfs_mount_t *mp) +{ + /* wait for all modifications to complete */ + while (atomic_read(&mp->m_active_trans) > 0) + delay(100); + + /* flush inodes and push all remaining buffers out to disk */ + xfs_quiesce_fs(mp); + + ASSERT_ALWAYS(atomic_read(&mp->m_active_trans) == 0); + + /* Push the superblock and write an unmount record */ + xfs_log_sbcount(mp, 1); + xfs_log_unmount_write(mp); + xfs_unmountfs_writesb(mp); +} + STATIC int xfs_mntupdate( bhv_desc_t *bdp, @@ -670,11 +694,8 @@ xfs_mntupdate( mp->m_flags &= ~XFS_MOUNT_BARRIER; } } else if (!(vfsp->vfs_flag & VFS_RDONLY)) { /* rw -> ro */ - bhv_vfs_sync(vfsp, SYNC_FSDATA|SYNC_BDFLUSH|SYNC_ATTR, NULL); - xfs_quiesce_fs(mp); - xfs_log_sbcount(mp, 1); - xfs_log_unmount_write(mp); - xfs_unmountfs_writesb(mp); + bhv_vfs_sync(vfsp, SYNC_DATA_QUIESCE, NULL); + xfs_attr_quiesce(mp); vfsp->vfs_flag |= VFS_RDONLY; } return 0; @@ -1952,9 +1973,9 @@ xfs_showargs( } /* - * Second stage of a freeze. The data is already frozen, now we have to take - * care of the metadata. New transactions are already blocked, so we need to - * wait for any remaining transactions to drain out before proceding. + * Second stage of a freeze. The data is already frozen so we only + * need to take care of themetadata. Once that's done write a dummy + * record to dirty the log in case of a crash while frozen. */ STATIC void xfs_freeze( @@ -1962,19 +1983,7 @@ xfs_freeze( { xfs_mount_t *mp = XFS_BHVTOM(bdp); - /* wait for all modifications to complete */ - while (atomic_read(&mp->m_active_trans) > 0) - delay(100); - - /* flush inodes and push all remaining buffers out to disk */ - xfs_quiesce_fs(mp); - - ASSERT_ALWAYS(atomic_read(&mp->m_active_trans) == 0); - - /* Push the superblock and write an unmount record */ - xfs_log_sbcount(mp, 1); - xfs_log_unmount_write(mp); - xfs_unmountfs_writesb(mp); + xfs_attr_quiesce(mp); xfs_fs_log_dummy(mp); } -- 2.39.5